DIESEL ENGINES NOISE COMPLIANCE

Model and Year: 1989 C, K, R, V, TRUCKS AND G, P VANS WITH 6.2L DIESEL ENGINE

A potential noise compliance issue has been discovered on 1989 model 6.2L diesel engines. It is MANDATORY that these units have the timing reset PRIOR TO VEHICLE SALE to avoid potential noncompliance to Federal, state, and local noise laws. Willfull violation of these laws can result in civil and/or criminal penalties. To correct this situation, the fuel injection pump timing must be reset on all affected units either in stock, or in-transit to your location PRIOR TO SALE of the vehicle. IMPORTANT: This procedure does not apply to vehicles that were sold and delivered prior to receipt of this bulletin or the preceding DCS Message 01-230 dated November 16, 1988.

VEHICLES INVOLVED

ALL vehicles with GVW's over 10,000 lbs (K or J in the 4th position of the VIN) must be reset. Vehicles under 10,000 lbs. GVW must be reset if they are to be sold in the following areas:

STATES

California Oregon Florida Washington Maryland Colorado Nevada

COUNTIES:

-------- Cook County, Illinois

LOCALITIES:

---------- Boston, MA Chicago, IL Des Plains, IL Grand Rapids, MI Madison, WI Prairie Village, KS Urbana, IL Washington, DC

The following VIN's represent the first engines reset by the assembly plants. Those vehicles (as well as those built after these VIN's) do not need to be reset by dealer personnel.

ASSEMBLY PLANT PRODUCT VIN Breakpoint -------------- ------- -------------- Flint Suburban/Utility KF 123336 Chev.

Janesville R/V Crew Cab/Cab Chassis KJ 110735 Chev.

Pontiac East C/K Pick-Up/Cab Chassis KE 140612 Chev.

Oshawa C/K Pick-Up/Cab Chassis Kl 138096 Chev.

Scarborough G-Van/Cutaway Chassis K4 120275 Chev.

Detroit Assembly P Model Chassis K3 312518 Chev.

Use the following procedure in resetting the injection pump timing:

For noise compliance, fuel injection pump timing on all 1989 6.2L diesels is to be reset using the static timing procedure. The static timing marks, straight lines on the pump and front housing, must be aligned. The engine must be off while the timing is being set.

STATIC TIMING PROCEDURE:

Adjust: (Reference Figure 13, Page 6C2-9 in 1989 Service Manual)

Injection Timing

- Loosen the three pump retaining nuts.

- Align the mark on the injection pump with the mark on the front cover (straight lines).

Tightenn

- Tighten pump retaining nuts to 40 Nm (30 ft. lbs.)

Use Labor Operation J5965 and appropriate Labor Time when submitting a warranty claim for this procedure.

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.